[no subject]

TCATOG2 is the categorical variable which violates the proportional hazards assumption. This is a tabulation of the variable:
. tab TCATOG2
STAGE: |
1=pTa; |
2=pT1; |
3=T2-T4 | Freq. Percent Cum.
------------+-----------------------------------
1 | 658 50.62 50.62
2 | 291 22.38 73.00
3 | 351 27.00 100.00
------------+-----------------------------------
Total | 1,300 100.00
value 1 are early tumours with better survival and are clearly masking the effect of later stage (value 3) tumours.
Should I create new dummy variables, test each for proportional hazards and re-write the model based upon this? I'm not sure how I should code up any new variables I create.
Best wishes
Tim
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